Heat pipe structure

ABSTRACT

A heat pipe structure includes a flat tubular body having a hollow section for contacting a heat source and at least one non-hollow section. A working fluid is contained in the hollow section and a capillary structure is disposed in the hollow section. The hollow section has a first outer side and a second outer side opposite to the first outer side. The non-hollow section is positioned on the first and second outer sides of the hollow section or a periphery thereof. The non-hollow section has a connection face for connecting with at least one retainer member.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a heat pipe structure, and more particularly to a thin heat pipe structure.

2. Description of the Related Art

A heat pipe has heat conductivity several times to several tens times that of copper, aluminum or the like. Therefore, the heat pipe has excellent performance and serves as a cooling component applied to various electronic devices. As to the configuration, the conventional heat pipes can be classified into heat pipes in the form of circular tubes and heat pipes in the form of flat plates. For cooling an electronic component such as a CPU, preferably a flat-plate heat pipe is used in view of easy installation and larger contact area. To catch up the trend toward miniaturization of cooling mechanism, the heat pipe has become thinner and thinner in adaptation to the cooling mechanism.

The heat pipe is formed with an internal space as a flow path for the working fluid contained in the heat pipe. The working fluid is converted between liquid phase and vapor phase through evaporation and condensation and is transferable within the heat pipe for transferring heat. The heat pipe is formed with sealed voids in which the working fluid is contained. The working fluid is phase-changeable and transferable to transfer heat.

The heat pipe is used as a heat conduction member. The heat pipe is fitted through or plug-in connected with a radiating fin assembly. The working fluid with low boiling point is filled in the heat pipe. The working fluid absorbs heat from a heat-generating electronic component (at the evaporation end) and evaporates into vapor. The vapor goes to the radiating fin assembly and transfers the heat to the radiating fin assembly (at the condensation end). A cooling fan then carries away the heat to dissipate the heat generated by the electronic component.

Currently, there are many methods for manufacturing the heat pipes. For example, the heat pipe can be manufactured in such a manner that metal powder is filled into a hollow tubular body and sintered to form a capillary structure layer on the inner wall face of the tubular body. Then the tubular body is vacuumed and filled with the working fluid and then sealed. Alternatively, a mesh capillary structure body is placed into a tubular body and sintered to form a capillary structure layer on the inner wall face of the tubular body. Then the tubular body is vacuumed and filled with the working fluid and then sealed. On the demand of the electronic equipment for slim configuration, the heat pipe must be made with a thin configuration.

Conventionally, the thin heat pipe can be fixed on a heat source in many manners. For example, a heat dissipation device includes a base seat, a heat pipe and a heat sink. The base seat has a receiving recess, a first half, a second half, two rib sections and four riveted sections. A first end of the heat pipe is received in the receiving recess and the heat sink is disposed on a second end of the heat pipe. The first end of the heat pipe extends through a through hole of one side of the base seat into the receiving recess. A retainer member is disposed on the base seat for fixing the first end of the heat pipe in the receiving recess. The retainer member can be a metal leaf spring, which is riveted on the riveted section of the base seat. In the case that the base seat is formed by means of die-casting and is not formed with any riveted section, the retainer member can be disposed on the base seat by means of screws, welding or any other suitable measure. After the retainer member is disposed on the base seat, the rib sections and the retainer member are positioned on the same side of the base seat.

In the above conventional technique, the total thickness of the heat dissipation device is the thickness of the heat pipe plus the thickness of the retainer member overlaid on the heat pipe plus the thickness of the base seat.

FIGS. 1A to 1C show another conventional technique for fixing the thin heat pipe on the heat source, including a flat heat pipe 10 and a base seat 11. A fixing arm 111 extends from each of four corners of the base seat to be fixed on a circuit board (not shown). The center of the base seat 11 is formed with an opening 112 for receiving a heat source such as a processor on the circuit board (not shown). The flat heat pipe 10 is connected to an upper face of the base seat 11, whereby the flat heat pipe 10 is bridged over the opening 112 in direct contact with the heat source. Preferably, two pairs of raised sections 113 are disposed on the upper face of the base seat 11 at intervals. The flat heat pipe 10 has such a width that the flat heat pipe 10 can be snugly received in the space defined between the raised sections 113. The flat heat pipe 10 can be connected to the base seat 11 by means of welding.

In the above conventional technique, the total thickness of the heat dissipation device is the thickness of the base seat plus the thickness of the heat pipe overlaid on the base seat.

In both the above conventional techniques, an additional cooperative structure such as a base seat is needed to fix the thin heat pipe on the heat source as a locking or support structure. The heat pipe is overlaid on and connected to the base seat. As a result, the total thickness is increased. This fails to meet the requirement for the current and future thin product.

It is therefore tried by the applicant to provide an improved thin heat pipe so as to reduce the thickness of the locking structure and thin the product.

SUMMARY OF THE INVENTION

It is therefore a primary object of the present invention to provide a heat pipe structure formed of a flat tubular body. The heat pipe structure can be fixed on a heat source without being overlaid on another structure such as a locking member. Therefore, the total thickness of the structure is reduced to meet the requirement for ultra-thin product.

It is a further object of the present invention to provide the above heat pipe structure in which the flat tubular body has non-hollow sections on two sides to connect with at least one retainer member for supporting or fixing the heat pipe structure.

It is still a further object of the present invention to provide the above heat pipe structure, which is connectable with at least one retainer member. The retainer member has such a thickness that the retainer member will not exceed an outer upper surface of the flat tubular body.

To achieve the above and other objects, the heat pipe structure of the present invention includes a flat tubular body. The flat tubular body includes a hollow section for contacting a heat source and at least one non-hollow section. A working fluid is contained in the hollow section and a capillary structure is disposed in the hollow section. The hollow section has a first outer side and a second outer side opposite to the first outer side. The non-hollow section is positioned on the first and second outer sides of the hollow section. The non-hollow section has a connection face for connecting with the retainer member.

Still to achieve the above and other objects, the heat pipe structure of the present invention is connectable with at least one retainer member to contact a heat source. The heat pipe structure includes a flat tubular body, which is formed of a hollow tubular body by means of flattening a tubular wall of the hollow tubular body. The tubular wall continuously surrounds an internal space of the hollow tubular body to define a diameter thereof. The flat tubular body includes: a hollow section formed by means of flattening the tubular wall for contacting the heat source, the hollow section having an upper board section, a lower board section and a chamber between the upper and lower board sections, a working fluid and a capillary structure being contained and disposed in the chamber, two opposite outer sides of the hollow section being respectively defined as a first outer side and a second outer side opposite to the first outer side; and at least one non-hollow section formed by means of flattening the tubular walls positioned on the first and second outer sides so as to press the tubular walls into contact with each other to form the non-hollow section. The non-hollow section has a connection face for connecting with the retainer member.

In the above heat pipe structure, the cross section of the hollow section has a horizontal central line. The non-hollow section is aligned with the horizontal central line or positioned below the horizontal central line.

In the above heat pipe structure, the capillary structure is formed on an inner surface of the chamber or supported between an inner upper surface and an inner lower surface of the chamber. The outer upper surface of the hollow section is higher than the connection face of the non-hollow section to define a first height. The non-hollow section has an attachment face.

In the above heat pipe structure, the non-hollow section extends from one end of the heat pipe structure along a heat pipe length of the heat pipe structure to the other end of the heat pipe structure or is formed on a contact section of the heat pipe length of the heat pipe structure.

The heat pipe structure of the present invention includes a flat tubular body. The flat tubular body is formed of a hollow tubular body by means of flattening a tubular wall of the hollow tubular body. The flat tubular body includes a hollow section for contacting the heat source and at least one non-hollow section for supporting or connecting with the retainer member. The heat pipe structure can be fixed on the heat source without being overlaid on another structure such as a locking member. Therefore, the total thickness of the structure is reduced to meet the requirement for ultra-thin product. Moreover, the components of the structure are simplified and the production efficiency is increased. Also, the number of the molds for manufacturing the heat pipe structure is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein:

FIG. 1A is a perspective exploded view of a conventional technique for fixing a thin heat pipe on a heat source;

FIG. 1B is a perspective assembled view of the conventional technique for fixing the thin heat pipe on the heat source;

FIG. 1C is a sectional view of the conventional technique for fixing the thin heat pipe on the heat source;

FIG. 2A is a sectional view of the hollow tubular body of the present invention;

FIG. 2B is a sectional view showing that the hollow tubular body is flattened into a flat tubular body;

FIG. 2C is a sectional view showing that the hollow tubular body is further flattened into a flat tubular body;

FIG. 3 is a sectional view of the flat tubular body of the present invention;

FIG. 4 is a sectional view of the flat tubular body of the present invention in another aspect;

FIG. 5A is a perspective exploded view of the retainer member and the non-hollow section of the heat pipe structure of the present invention;

FIG. 5B is a perspective assembled view of the retainer member and the non-hollow section of the heat pipe structure of the present invention;

FIG. 5C is a sectional view taken along line X-X′ of FIG. 5B;

FIG. 6 is a perspective exploded view of the retainer member and the non-hollow section of the heat pipe structure of the present invention in another aspect; and

FIG. 7 is a perspective view showing the connection between the heat pipe structure of the present invention and a heat dissipation unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIGS. 2C, 2B, 2C and 3. The heat pipe structure 20 of the present invention includes a flat tubular body 21 (as shown in FIG. 3). The flat tubular body 21 is formed of a tubular body P by means of flattening the tubular wall P1 of the tubular body P (as shown in FIGS. 2A, 2B, 2C). The tubular wall P1 continuously surrounds an internal space of the tubular body P to define a diameter D thereof. In this embodiment, the tubular body P is, but not limited to, a circular tubular body. Alternatively, the tubular body P can be a tubular body with a D-shaped cross section or otherwise shaped cross section.

As shown in FIG. 3, the flat tubular body 21 includes a hollow section 22 and at least one non-hollow section 23. The hollow section 22 is formed by means of flattening the tubular wall P1 (as shown in FIGS. 2A, 2B, 2C). The hollow section 22 has an upper board section 221, a lower board section 222 and a chamber 223 between the upper and lower board sections 221, 222. A working fluid (not shown) and a capillary structure 224 are contained and disposed in the chamber 223. A left side and a right side of the hollow section 22 are respectively defined as a first outer side 225 and a second outer side 226.

The non-hollow section 23 is formed by means of flattening the tubular walls P1 positioned on the first and second outer sides 225, 226 (as shown in FIGS. 2A, 2B, 2C) so as to press the tubular walls P1 of the first and second outer sides 225, 226 into contact with each other to form the non-hollow section 23. The non-hollow section 23 has a connection face 231.

To speak more specifically, the circular hollow heat pipe P of FIG. 2A is first-time flattened by means of a mechanical processing apparatus such as a mechanical transmission or air transmission press apparatus. In the first-time flattening process, the hollow heat pipe P is not completely flattened. Instead, the hollow heat pipe P is only flattened into a flat hollow heat pipe P (as shown in FIG. 2B). Then the left and right sides of the central section of the flattened hollow heat pipe P are further flattened so as to press the tubular walls P1 (the upper and lower tubular walls P1 as shown in the drawings) of the left and right sides of the flattened hollow heat pipe P into contact with each other to form the non-hollow section 23 (as shown in FIG. 2C). The remaining central section forms the hollow section 22.

Further referring to FIG. 3, the upper and lower board sections 221, 222 of the hollow section 22 are raised and higher than and lower than the non-hollow section 23 respectively. An outer upper surface 2211 of the upper board section 221 is higher than the connection face 231 of the non-hollow section to define a first height (or thickness) hl. Moreover, in practice, the hollow section 22 is not limited to the above configuration. Alternatively, as shown in FIG. 4, the upper board section 221 of the hollow section 22 is raised and higher than the non-hollow section 23, while the lower board section 222 a is in the form of a plane board in flush with the non-hollow section 23 to define a coplanar face AA. In addition, as shown in FIG. 3, the capillary structure 224 in the chamber 223 is supported between an inner upper surface 2231 and an inner lower surface 2232 of the chamber 223.

Further referring to FIGS. 5A, 5B and 5C, in practice, the hollow section 22 serves to contact a heat source 26, while the non-hollow section 23 serves to support or connect with at least one retainer member 24. The retainer member 24 is connected to the connection face 231 by means of welding or other connection measure. The cross section of the retainer member 24 has a second height (or thickness) h2 substantially equal to or smaller than the first height (or thickness) h1 (as shown in FIG. 3). That is, in practice, the retainer member 24 connected to the connection face 231 has such a thickness that the retainer member 24 will not exceed the outer upper surface 2211 of the upper board section 221 of the hollow section 22.

Also, as shown in FIG. 5A, the non-hollow section 23 extends from one end (start end) of the heat pipe structure 20 along a heat pipe length L1 of the heat pipe structure 20 to the other end (terminal end) of the heat pipe structure 20. Alternatively, the non-hollow section 23 is only formed on a section L2 of the heat pipe length L1 of the heat pipe structure 20.

Finally, referring to FIG. 7, the end of the heat pipe structure 20, which end is connected to the retainer member 24 is connected to the heat source 26 (as shown in

FIG. 5A). The other end of the heat pipe structure 20 is connected to a heat dissipation unit 30 (such as a cooling fan and a radiating fin assembly). Accordingly, the heat pipe structure 20 can transfer the heat of the heat source 26 to the heat dissipation unit 30 to dissipate the heat (as shown in FIG. 5A).

In conclusion, in the present invention, the hollow tubular body is flattened to form a flat tubular body having a hollow section in contact with a heat source and a non-hollow section directly connected to a retainer member. In this case, it is unnecessary to overlay the heat pipe structure on another structure. Moreover, the height of the retainer member is limited not to exceed the height of the hollow section and the non-hollow section so that the total height (or thickness) of the heat pipe structure and the retainer member is reduced to meet the requirement for ultra-thin product.

The present invention has been described with the above embodiments thereof and it is understood that many changes and modifications in the above embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims. 

What is claimed is:
 1. A heat pipe structure connectable with at least one retainer member, the heat pipe structure comprising a flat tubular body including: a hollow section for contacting a heat source, a working fluid being contained in the hollow section and a capillary structure being disposed in the hollow section, the hollow section having a first outer side and a second outer side opposite to the first outer side; and at least one non-hollow section positioned on the first and second outer sides of the hollow section, the non-hollow section having a connection face for connecting with the retainer member.
 2. A heat pipe structure connectable with at least one retainer member to contact a heat source, the heat pipe structure comprising a flat tubular body, which is formed of a hollow tubular body by means of flattening a tubular wall of the hollow tubular body, the tubular wall continuously surrounding an internal space of the hollow tubular body to define a diameter thereof, the flat tubular body including: a hollow section formed by means of flattening the tubular wall for contacting the heat source, the hollow section having an upper board section, a lower board section and a chamber between the upper and lower board sections, a working fluid and a capillary structure being contained and disposed in the chamber, two opposite outer sides of the hollow section being respectively defined as a first outer side and a second outer side opposite to the first outer side; and at least one non-hollow section formed by means of flattening the tubular walls positioned on the first and second outer sides so as to press the tubular walls into contact with each other to form the non-hollow section, the non-hollow section having a connection face for connecting with the retainer member.
 3. The heat pipe structure as claimed in claim 2, wherein the upper and lower board sections of the hollow section are raised and higher than and lower than the non-hollow section respectively.
 4. The heat pipe structure as claimed in claim 2, wherein the upper board section of the hollow section is raised and higher than the non-hollow section, while the lower board section is in the form of a plane board in flush with the non-hollow section to define a coplanar face.
 5. The heat pipe structure as claimed in claim 2, wherein the capillary structure in the chamber is supported between an inner upper surface and an inner lower surface of the chamber.
 6. The heat pipe structure as claimed in claim 2, wherein the outer upper surface of the upper board section of the hollow section is higher than the connection face of the non-hollow section to define a first height.
 7. The heat pipe structure as claimed in claim 6, wherein the cross section of the retainer member has a second height, which is substantially equal to or smaller than the first height.
 8. The heat pipe structure as claimed in claim 2, wherein the non-hollow section extends from one end of the heat pipe structure along a heat pipe length of the heat pipe structure to the other end of the heat pipe structure.
 9. The heat pipe structure as claimed in claim 2, wherein the non-hollow section is formed on a section of a heat pipe length of the heat pipe structure. 